1Shop for shoes late in the day when your feet are at their largest.

If you plan to wear socks with the shoes, bring the appropriate pair—dress socks for dress shoes, athletic socks for athletic shoes. Stand up when you place your foot in the Brannock measuring device for the best representation of your foot size and shape while walking.

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2Ask a store associate to measure both of your feet.

Many people’s feet vary in size from one to the other, and it’s important to select a shoe based on the fit of the longer foot. If you have time to measure only one foot, go with the left, which tends to be the longer of the two. Experts suggest getting fitted every time you shop and at least once a year.

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3Be aware that width is just as important as length.

If you have a narrow or a wide foot, invest in brands that offer a variety of widths. If you aren’t sure whether a shoe is wide enough, trace the outline on paper and place your foot inside. If your foot spills over, the shoe is too narrow.

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4Be open to a new size.

Many people feel committed to a specific number, which may be wrong. Sizes can differ, in both length and width, by as little as a few millimeters. If you are usually a size 10.5 D, the standard medium width, you might want to try a size 11 C, for a slightly longer, narrower shoe.